Air hammer mandrel press



Nov. 10, 1964 A. J. DONOFRIO AIR HAMMER MANDREL PRESS 2 Sheets-Sheet 1 Filed June 22. 1962 INVENTOR. ANGELO .J. DONOF RIO Nov. 10, 1964 A. J. DONOFRIO 3,156,038

AIR HAMMER MANDREL PRESS INVENTOR. ANGELO J. DONOF RIO ATTYS.

United States Patent York Filed June 22, 1962, Ser. No. 204,358 3 Claims. (Cl. 29-234) The present invention relates to an apparatus and method for positioning a mandrel within a cylinder bore and more particularly to apparatus for inserting in or removing a tapered mandrel positioned within a tapered bore of a copper printing roll.

The rollers used in fabric and other printing machines are conventionally made from a gravured copper cylinder having a tapered bore and a tapered mandrel positioned within the bore. It is common practice to remove the mandrel from the copper roll and utilize the mandrel with other rolls. It has been the prior art practice to position the roll on a truck and manually insert the tapered mandrel therein. A plurality of workmen hold the roll while a heavy metal object suspended from a chain is used as a pendulum to drive the mandrel into the copper cylinder. This operation is extremely dangerous, time consuming, and is not an eflicient use of labor.

It is the general object of the invention to avoid and overcome the foregoing and other difficulties of and objections to the prior art practices by the provision of a relatively simple and inexpensive method and apparatus for accurately and efficiently inserting and removing mandrels from cylinder bores.

Another object of the invention is to provide a method and apparatus for safely handling and inserting a tapered mandrel into a tapered cylindrical bore.

Another object of the invention is the provision of a method and apparatus of coupling an impact force with a constant pressure to position a mandrel into a hollow cylinder.

Another object of the invention is to provide in an apparatus for inserting mandrels into cylinder bores accurate control means to regulate the pressure on the mandrels thereby completely eliminating any oversiding.

According to the invention, the mandrel is positioned in the bore of a hollow cylinder by manually placing the mandrel in the bore, then forcing the mandrel further into the bore with a constant pressure and subsequently moving the mandrel in its final position with an impact force.

The apparatus of the invention utilizes a hammer assembly and a movable mandrel and cylinder supporting truck. The truck is releasably connected to the frame supporting the hammer assembly so that the hammer assembly engages one end of the mandrel. The hammer assembly is moved by power means such as a pair of screws to force the mandrel into the cylinder under a constant pressure.

A heavy mass moved by fluid pressure such as air pressure engages the portion of the end of the mandrel to apply an impact force thereto. The amount of impact force is controlled by the regulation of the fluid pressure.

The exact nature of the invention as well as other objects and advantages thereof will be apparent from a consideration of the following specification relating to the annexed drawing in which:

FIG. 1 shows an elevation view, partly in section, of a "ice hammer press coupled to a mandrel and cylinder supporting truck.

FIG. 2 is a sectional view of the hammer press of FIG. 1 taken along the line 22.

FIG. 3 is a sectional view of the hammer press of FIG. 1 taken along the line 33.

Referring to the drawing, there is shown in FIG. 1 a hammer press 10 releasably coupled to a work supporting truck 12. The press 10 has a skeleton frame 14 supporting a pair of parallel T-shaped rails 16 and 18. The rails are secured to the upper portion of the frame 14 and extend longitudinally thereof to slidably support the hammer assembly 20.

The hammer assembly 20 as shown in FIG. 3 is substantially rectangular shaped and includes a bottom plate 22, a top plate 24, and side plates 26 and 28. A pressure plate 30 is secured to the forward end of the hammer assembly. To slidably mount the hammer assembly on the key-shaped rails, two pairs of channel-shaped guides 32 and 34 are secured to the lower surface of the bottom plate 22 and extend downwardly over the cross portion of the T-shaped rails 16 and 18.

As best shown in FIG. 2 the hammer assembly 20 is moved by a pair of longitudinally extend-ing screws 36 and 38. The ends of the screws are mounted on portions of the frame 14 by thrust bearings 40, 42, 44, 46. The screws are positioned in the vertical plane formed by the T-shaped rails 16 and 18 and extend parallel thereto. A pair of longitudinally spaced threaded blocks 48 and 59 secured to the side plate 26 drivably connects screw 36 to the hammer assembly 29. A pair of longitudinally spaced threaded blocks 52 and 54 secured to the wide plate 28 drivably connects the screw 38 to the hammer assembly 2%.

The power source to drive the hammer assembly along the T-shaped rails comprises a reversible motor 56 secured to the frame 14 and a gear reducer 58. A power transmission means 60 such as a chain and sprockets drivably connects the motor with the gear reducer. The output shaft 62 of the gear reducer is drivably connected to the ends of each screw 36 and 38 by a power transmission means 64 such as a chain and sprockets. The motor 56 operates through the gear reducer to simultaneously rotate the screws in either a clockwise or counterclockwise direction to move the hammer press relative to the T-shaped rails 16 and 13.

The hammer assembly 26 includes a double acting fluid motor 66, preferably an air cylinder, having a piston 68 and a piston rod 76. The piston rod'70 is connected to a relatively heavy mass 72 so that the movement of the mass 72 is equal to the stroke of the piston 68. A tempered steel punch 74 extends longitudinally from the mass 72 through the pressure plate 30. Upper and lower rollers 76 and 78 journalled on pins 80 and 82 support the mass 72 within the hammer assembly. Channel-shaped guide members 84 and 86 secured to the top and bottom plates of the hammer assembly provide tracks for the rollers.

A conventional slide valve 38 having a manually operable lever 89 is operable to regulate the amount of pressure in the fluid motor. A flexible inlet conduit 90 connects the valve 88 with the fluid pressure source.

In order to center the mandrel relative to'the punch.

74, a sleeve 92 is secured to the forward surface of the pressure plate 30. The diameter of the sleeve is slightly larger than the diameter of the end of the mandrel shaft adapted to be moved relative to a hollow cylinder. An impact block 94 of malleable iron is positioned within the bore of the mandrel sleeve between the punch and the end of the mandrel to reduce the impact damage to both the end of the punch and the end of the mandrel.

The handling of the mandrel is eliminated by the use of the truck 12.

As shown in FIG. 1, the truck 12 is constructed with a longitudinally extending top frame 96 and a sub-frame 98. Casters 1G9 and 102 pivotally mounted on the lower surface of the sub-frame 98 permit the truck to be relocated by a tractor connected to the tongue 104. To permit the vertical adjustment of the top frame 95, a plurality of vertical adjustable legs 106 and 108 interconnect the top frame with a sub-frame. Wheel nuts 110 and 112 threadably engage the studs 114 and 116 and are rotatable to vertically adjust the length of the legs.

Secured to the top surface of the top frame are two pairs of vertically extending undercut rail members 118 and 120. The rail members form T-shaped slots which are used to position work-supporting jigs or work holders on the top frame.

The work jig or roll and mandrel holder 122 supports the roll 124- and mandrel 126 in the plane of movement of the hammer assembly 20. As shown in FIG. 1, the mandrel has a tapered mid-portion which extends into a tapered bore within the cylinder or roll 124. The hammer assembly is forcing the mandrel into the bore of the roll. In order to remove the mandrel from the roll the roll is turned 180 degrees and the hammer assembly applies force to the opposite end of the mandrel moving the mandrel from the cylinder or roll.

The work jig 122 contains a horizontal support plate 128 and a vertical thrust plate 130. The thrust plate 130 has an upwardly extending U-shaped slot which has sufficient clearance to permit the mandrel to move through said plate and hold the roll 124 to permit relative movement between the roll and mandrel. A pair of transversely extending T-shaped beams 132 and 134 are secured to the lower surface of the support plate 128. The beams slide in the T-shaped channels formed by the rail members 118 and 120. The work jig is fixedly secured to the truck and is readily replaceable therefrom.

A lock means 136 is operable to releasably secure the support plate 128 of the work jig to the hammer press frame 14. The lock means 136, as shown in FIG. 2, includes a disc 138 pivotally mounted on a vertical pin secured to the support plate 128 and pair of laterally extending rod 140 and 142. The rods are pivotally mounted on the disc 138 and extend through guides 146 and 148. The outer ends of the rods extend through openings 150 and 152 in the hammer press frame 14. Rotation of the disc 138 by means of a handle 154 moves the rods 140 and 142 to engage and disengage the frame 14.

In order to insert the mandrel into the bore of the cylinder 124 the cylinder is placed on the jig 122 and the mandrel 126 is manual positioned within the bore. The truck is moved adjacent the hammer press frame 14 so that the lock 136 is operative to secure the jig to the frame 14. If the axis of the mandrel is not in alignment with the axis of the hammer assembly 20, the wheel nuts 110 and 112 are manually rotated to adjust the position of the mandrel relative to the hammer assembly. The bore of the mandrel sleeve 92 must be in alignment with the end of the mandrel 126.

When the motor 56 is energized the screws 36 and 38 drive the hammer assembly 20 toward the mandrel. As shown in FIG. 2, the mandrel 126 engages the impact block 94 which is seated on the pressure plate 30. The mandrel 126 is moved with the hammer assembly with a constant pressure into the bore of the roll 124.

The final positioning of the mandrel is accomplished by striking the impact block 94 with the punch 72. The manual operation of the valve 88 regulates the fluid pressure in the fluid motor 66 to adjust the stroke of the piston 68. The movement of the mass 72 corresponds to the stroke of the piston 68. The amount of pressure in the fluid motor determines the impact force of the punch 74 on the impact block and end of the mandrel 126.

While there have been shown, described, and pointed out the fundamental novel features of the invention as applied to the preferred embodiment, it will be understood that various omissions, substitutions, changes in form, and details of the apparatus illustrated may be made by those skilled in the art, without departing from the spirit of the invention. It is intended to be limited only by the scope of the following claims.

What is claimed is:

1. In combination,

a frame,

a hammer assembly mounted on the frame for movement in an elongated path,

means for moving the hammer assembly in the elongated path,

a portable truck for supporting a mandrel and a hollow cylinder including lock means to releasably secure the truck to the frame to prevent any relative movement therebetween and so that the axis of the mandrel lies in the elongated path,

a support to hold the cylinder in a fixed position in the elongated path, and

adjustable legs to adjust the position of the mandrel relative to the hammer assembly, and

means slidably coupling the hammer assembly with one end of the mandrel whereby the movement of the hammer assembly forces the mandrel into the cylinder.

2. In combination,

a frame,

a hammer assembly mounted on the frame for movement in an elongated path,

means for moving the hammer assembly in the elongated path,

weight means mounted within the hammer assembly for movement in the elongated path,

a wheeled portable truck for supporting a mandrel in a hollow cylinder including lock means to releasably secure the truck to the frame to prevent relative movement therebetween and so that the axis of the mandrel lies in the elongated path, a support to hold the cylinder in a fixed position in the elongated path, and adjustable legs to adjust the position of the mandrel relative to the hammer assembly, means slidably coupling the hammer assembly with one end of the mandrel whereby the movement of the hammer assembly forces the mandrel into the cylinder, and

an impact block positioned within said coupling means engaging a portion of the weight means and said end of the mandrel whereby selective movement of the weight means toward the mandrel will apply an impact force thereto.

3. In combination,

a frame,

a hammer assembly mounted on the frame for movement in an elongated path,

means for moving the hammer assembly in the elongated path,

a portable truck for supporting a mandrel and a hollow cylinder including lock means to releasably secure the truck to the frame to prevent any relative movement there- 5 between and so that the axis of the mandrel lies in the elongated path, and a support to hold the cylinder in a fixed position in the elongated path, and means slidably coupling the hammer assembly with one end of the mandrel whereby the movement of the hammer assembly forces the mandrel into the cylinder.

References Cited by the Examiner 1,723,730 8/29 Haight 173112 X 1,876,922 9/32 Hamilton.

1,927,598 9/33 Schlichter.

2,274,670 3/42 Curtis 173-112 X 2,338,157 1/44 Allen 173l12 X 2,434,832 1/48 Bruun 29-446 2,863,357 12/58 Peterson 29446 3,003,231 10/61 Tiess et a1. 29252 X 3,035,335 5/62 Fry 29-234 3,061,914 11/62 Johnston 29234 WILLIAM FELDMAN, Primary Examiner.

WHITMORE WILTZ, MILTON S. MEI-IR, Examiners. 

3. IN COMBINATION, A FRAME, A HAMMER ASSEMBLY MOUNTED ON THE FRAME FOR MOVEMENT IN AN ELONGATED PATH, MEANS FOR MOVING THE HAMMER ASSEMBLY IN THE ELONGATED PATH, A PORTABLE TRUCK FOR SUPPORTING A MANDREL AND A HOLLOW CYLINDER INCLUDING LOCK MEANS TO RELEASABLY SECURE THE TRUCK TO THE FRAME TO PREVENT ANY RELATIVE MOVEMENT THEREBETWEEN AND SO THAT THE AXIS OF THE MANDREL LIES IN THE ELONGATED PATH, AND A SUPPORT TO HOLD THE CYLINDER IN A FIXED POSITION IN THE ELONGATED PATH, AND MEANS SLIDABLY COUPLING THE HAMMER ASSEMBLY WITH ONE END OF THE MANDREL WHEREBY THE MOVEMENT OF THE HAMMER ASSEMBLY FORCES THE MANDREL INTO THE CYLINDER. 